int buildminheap(struct heap*q,int heapsize)
{
int i;
for (i=heapsize/2;i>=1;i--)
minheapify(q,i,heapsize);
return 0;
}
struct node * extractmin(struct heap *q,int heapsize)
{
struct heap tmp;
tmp=q[1];
q[1]=q[heapsize];
minheapify(q,1,heapsize-1);
return tmp.hnode;
}
void buildminheap(Heap heap)
{
int i;
for(i = heap.length - 1; i >= 0; i--)
{
minheapify(heap, i);
}
}
int minvalue(node arr[],int* size)
{
int min = arr[1].value;
swap(arr,1,*size);
*size = *size - 1;
minheapify(arr,1,*size);
return min;
}
HeapNode *delminimal(Heap *heap)
{
HeapNode *minimal = heap->a[0];
//sawp the last element with the minimal element
//then dec the heap size
heap->a[0] = heap->a[--(heap->length)];
minheapify(*heap, 0);
return minimal;
}
int extract_min(int n,int a[n]){
if(n<1){
printf("underflow");
return -1;
}
int min;
min=a[1];
a[1]=a[n];
n=n-1;
minheapify(n,a,1);
return min;
}
void minheapify(int n,int a[n],int i){
int l,r,min=i;
l=2*i;
r=l+1;
if(l<=n && a[l] < a[i])
min=l;
if(r<=n && a[r] < a[l])
min=r;
if(min!=i) {
a[min] = a[i] + a[min] - (a[i] = a[min]);
minheapify(n,a,min);
}
}
void minheapify(node arr[],int i,int size)
{
int left = 2*i;
int right = 2*i+1;
int minimum = i;
if(left<=size && arr[left].prior<arr[minimum].prior){
minimum = left;
}
if(right<=size && arr[right].prior<arr[minimum].prior){
minimum = right;
}
if(i!=minimum){
swap(arr,i,minimum);
minheapify(arr,minimum,size);
}
}
void minheapify(Heap heap, int i)
{
int l = LEFT(i);
int r = RIGHT(i);
int minimal = i;
if(l < heap.length && heap.a[l]->key < heap.a[i]->key)
minimal = l;
if(r < heap.length && heap.a[r]->key < heap.a[minimal]->key)
minimal = r;
if(minimal != i)
{
HeapNode *temp = heap.a[i];
heap.a[i] = heap.a[minimal];
heap.a[minimal] = temp;
minheapify(heap, minimal);
}
}
int main()
{
int arr[MAX_SIZE], size, i;
printf("Enter size of the array...\n");
scanf("%d", &size);
printf("Enter the array of integers...\n");
for(i=0;i<size;i++)
scanf("%d", &arr[i]);
printf("Input array is:\n");
display(arr, size);
//ascending order
for (i = 0; i < size; i++)
{
heapify(arr, 0, size-i);
swap(arr+0, arr+(size-i-1));
}
printf("\nAscending order:\n");
display(arr, size);
//descending order
for (i = 0; i < size; i++)
{
minheapify(arr, 0, size-i);
swap(arr+0, arr+(size-i-1));
}
printf("\nDescending order:\n");
display(arr, size);
return 0;
}
void buildheap_min(int n,int a[n]){
int j;
for(j=n/2;j>=1;j--){
minheapify(n,a,j);
}
}